Find out about the decades long search for water on Mars
Water on Mars
Mars was a world of rivers oceans even some astronomers said artificial canals serving Martian cities but today the planet is a desolate wasteland. Throughout history, people imagine Mars might be a planet like our own perhaps even our twin. Through telescopes, early astronomers thought they saw seas and continents even vegetation that changed with the seasons it seemed that many people agreed there must be water on Mars so the first actual photographs from the surface were a shock. This barren desert landscape wasn’t at all what many had imagined. Mars seemed of freezing dead world nothing like our own.
As we began to study the planet up close the mystery deepened, orbiters showed surface features that certainly looked like they had been carved by flowing water shorelines deltas oceans islands and continents nearly 40,000 river valleys perhaps the very channels that those early astronomers claimed to have seen were these features created by liquid. As we sent more and more probes and Rovers to circle and roamed the planet the evidence that the landscape had been shaped by water grew stronger and stronger, but it wasn’t until 2012 that NASA’s Curiosity Rover finally proved beyond all doubt that liquid water had flowed across Mars exploring its landing site in Gale crater. Curiosity imaged what had to be an ancient streambed these pebbles were rounded and weathered in a way that only liquid water could have managed and it seems there hadn’t been just a small amount of water on Mars using the geological evidence found in the ancient rocks and clays scientists have estimated that there could have been enough water to submerge the whole planet in an ocean up to a mile deep in the early solar system perhaps Mars and earth really had been very alike. So what happened? The question was so crucial that for its missions in the 1990s and 2000s NASA set itself a simple goal follow the water there were already signs that Mars wasn’t a completely arid world in 1976 the Viking one and two Landers confirmed the presence of water vapor in the atmosphere other experiments strongly suggested water chemically bound in the Martian soil as later probes explored more and more evidence was found of water locked in minerals. On earth, this water would be released periodically by volcanic and tectonic activity, but Mars has little such activity if any so the water there has remained trapped in the rocks and soils for billions of years. It was the first clue where the water may have gone but water in rocks wouldn’t sustain human life on Mars future explorers and settlers might be able to extract some of it by literally cooking the rocks, but the energy and time involved would be immense and still produce very little. In July 2003 though it was announced that the Mars Odyssey orbiter had detected huge amounts of water ice on Mars. We knew the red planet had ice caps of frozen carbon dioxide but now finally there was proof of frozen water to just inches from the surface those results were confirmed in 2008 when the phoenix spacecraft sent incredible images from the Martian polar region that strangely shaped landscape is ice hidden by a layer of dust so thin that the probe itself could dig down and revealed the ice beneath.